Investigation of Dielectric and Piezoelectric Properties of Polyvinylidene Fluoride Films Reinforced with Anatase Phase Titanium Dioxide for Pressure Sensing

In the present study, anatase phase titanium dioxide (A-TiO₂)-reinforced polyvinylidene fluoride (PVDF) nanocomposite films are synthesized by the solvent casting method. The electroactive phase, dielectric, and piezoelectric properties are studied for A-TiO₂ nanoparticles at 0.8 wt.%, 1.6 wt.%, 2.4 wt.%, 3.2 wt.%, and 4.0 wt.% content in the PVDF matrix. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy are used to assess the structural properties and the enhancement in the electroactive β phase, respectively. The β phase is found to improve up to 77%. Atomic force microscopy (AFM) shows that the roughness of the films increases with an increase in the amount of reinforcement. The dielectric constant (ε′) and dissipation factor are found to vary with filler weight percentage and frequency. The dielectric constant increases to 24.45 for 2.4 wt.% of A-TiO₂ nanoparticles. The piezo-response increases significantly from 0.6 V to 1.3 V for the nanocomposite in comparison to pure PVDF films. The results of the current study show numerous potential applications in energy-harvesting pressure sensors.